The Metal-Era Learning Center

This article discusses the importance of ventilation and its critical impact in different regions.

• For a discussion on the different types of ventilation for sloped roofs, their environmental impacts, and their ventilation requirements, see Types of Ventilation & Guidelines.
• For a discussion on how to calculate the proper information to select the right products for use on your building projects, see Proper Ventilation Calculation for Product Selection.

Why is it important for your building to to have proper ventilation?

Your ventilation system can extend the life of the entire roof system, especially shingled roofs in warm regions, by minimizing the temperature differential between the attic air and the outside air. This helps prevent condensation, mold, and ice dam formation while improving sustainability through efficient energy usage.

Benefits in Warm Regions

In warm regions and/or during the dog days (and months!) of summer, proper ventilation on your building will help keep the roof cool, ultimately extending its lifespan. Keeping your roof cool is important, as excess heat can cause shingles to curl and deteriorate. 

Example (Fig. 1): Without proper ventilation, the left side of the attic is heating up to roughly 140 degrees, causing the roof sheathing to be 170 degrees. Meanwhile, the right side has a solid ventilation setup in place, resulting in the attic being roughly 25 degrees cooler while helping prevent premature shingle deterioration.

Studies conducted by Oak Ridge National Laboratories found that ventilation can reduce the heat gain through the roof assembly up to 45% when compared to an unvented system. 

Benefits in Cold Regions

In cold regions and/or during winter months, proper ventilation helps minimize the temperature differential between the attic and the outside air (Fig. 2), thus reducing the risk of moisture buildup that can cause rust and corrosion on metal roofs, insulation damage, and mold/mildew.

One of the biggest benefits of proper ventilation is preventing freezing/thaw cycles that cause ice dams. There are three key elements to preventing ice dams:

1. Proper insulation (see the U.S. Department of Energy recommended R-values for each region)

2. Proper ventilation

3. Use of ice and water shields

Proper Insulation

The U.S. Department of Energy has specific recommendations to properly insulate a building based on the climate, type of heating and cooling system, and the part of the building you plan to ventilate.

Proper Ventilation At-A-Glance

• Proper ventilation minimizes the temperature differential between the attic and outside air

• ​This prevents freeze/thaw cycles that cause ice dams by bringing in outside air at the eave and exhausting it at the ridge

​Questions on proper ventilation? Reach out to our team of experts today!